The headrest is fitted to the upper part of the seat back of the vehicle seat and is formed with a surface material, a headrest stay and a foamed body. The surface material forms the outer contour, the headrest stay is the skeleton member, and the foamed body is filled and foamed in the headrest. Recently, headrests including impact-absorbing members have been developed. (See, for example, patent document 1 below.) The impact-absorbing member reduces the impact to the head and neck of the occupant at the time of a rear collision, and it supports the head more stably.
The surface material of the headrest has an opening. In the production of the headrest, the absorbing member is mounted on the headrest stay, and then it is inserted into the surface material through the opening. The opening is made large to facilitate insertion. Because of the large opening, there may be leakage of the foaming material from the opening at the time of foaming, and the appearance of the headrest may be impaired.
It is possible to sew the opening to prevent leakage of the foaming material. But local tensile force acts on the surface material around the opening at the time of foaming, and in the process of forming the foamed body by the reaction of the foaming material injected into the surface material, the surface material is not uniformly expanded, and wrinkles form on the part where the local tensile force acts. As a result, the appearance of the headrest is impaired.
In view of those problems, in the headrest disclosed in patent document 1, the size of the opening of the surface material is set to a minimum size, the impact-absorbing member and the headrest stay are each separately inserted into the headrest, and the impact-absorbing member and the headrest stay are assembled in the headrest. An inclined guide surface and an engagement part for the headrest stay are fitted to the impact-absorbing member in order to facilitate assembly.